SAN FRANCISCO — When U.S. presidential debates reveal all the class of a school-cafeteria food fight, it’s time to acknowledge that bad taste has infiltrated American culture to its roots. San Francisco Ballet’s often cheesy “Swan Lake” might be included in this spread of kitsch, except that the ballet’s flaws are ultimately overshadowed by choreography that, at its core, is sublime, as the Friday-night performance at the War Memorial Opera House proved.

In 1940, San Francisco Ballet became the first U.S. company to have the complete “Swan Lake” in its repertory, one of the gems handed down from 19th-century tsarist Russia. In 1988 the company’s new artistic director, Helgi Tomasson, introduced his own interpretation by resurrecting much of the venerated 1895 version by Marius Petipa/Lev Ivanov. In 2009 Tomasson overhauled the classic with the assistance of Broadway designer Jonathan Fensom and “modernized” the fairy tale.

For this latest version, Tomasson felt it necessary to add back story in the form of a prologue, with the intention of making the tale intelligible, and ensuring that it belonged to the swan-woman Odette.

The prologue, however, almost entirely cements this as a contest between two men — the evil sorcerer Von Rothbart, who molests Odette and transforms her into a swan, and Prince Siegfried, who steals her heart.

These two guys (Von Rothbart resembles Lord Byron crossed with a vampire from “Buffy the Vampire Slayer”) battle each other through the woman, who is a prisoner of them both. Add in the production’s visual brashness, which injects endless distractions and unintentional humor, and it’s a wonder the ballet has survived.

But survive it does. Despite being bleached of mystery, despite the disturbing gender politics and the camp elements in costume and decor — — including Busby Berkeley-style feather caps, a gold staircase reminiscent of Liberace and a sci-fi moon — — this remains Odette/Odile’s story.

On Friday, it was Yuan Yuan Tan playing Odette, with Tiit Helimets as Prince Siegfried, who was entrusted with communicating the trapped young woman’s plight.

Tan, who has been with the company since 1995, is a physically glorious dancer with arms like tendrils, feet like railroad spikes and hips that are both supple and steely. No one can extend a leg as high and then tuck it in with such pristine geometry as she. Although she is foremost a legato dancer, Tan can also jolt into action when given roles such as the devilish Odile, Odette’s destructive alter ego.

In the Friday performance, Tan’s Odette never emerged from her trance. Discovered by the Prince, who has gone out to hunt with a new crossbow on the night of his 21st birthday, her Odette was unable to reveal the swan-woman’s internal struggle, in which she shifts from timorous to open, from captive to queen, and then back. Instead, Tan floated from one state to the next, and where the phrases demanded a kaleidoscope of color, she consistently maintained a cool elegance.

Nowhere was this more striking than in Act 2, when Siegfried and Odette perform one of the most breathtaking pas de deux in ballet history. Rather than being swept up in unfolding passion, she and her prince danced a clinical declaration of love, with Helimets’ Siegfried as impeccably correct as Tan’s Odette. Even though Tan’s foot beat furiously against her ankle, suggesting the action of her heart, there were no tears spilled over these young lovers. They never transcended the sheer technical rigor of their roles.

Not, at least, until Tan caught our eye at the ball in Act 3, whereas Odile — — Von Rothbart’s daughter transformed into Odette’s doppelgänger — — Tan becomes a vixen (think Audrey Hepburn gone bad). But Helimets doesn’t meet her frenzy with his own. In fact, his Siegfried seems totally oblivious that he is being seduced, then vanquished, until Odette’s trapped form appears at the top of the stairs. Only then is his betrayal is clear.

If acting was neither lead’s strong suit, the couple nevertheless ticked off their tour en l’air, whipping turns, backbends and fierce partnering with elegance and surety.

They were in good company, considering the troupe’s sterling performances of the national dances in Act 3 and in the Act 1 Pas de Trois with Dores André, Taras Domitro and Sasha De Sola, who combined impeccable technique with virtuosic style.

Friday’s cast of signets — the iconic quartet of swans who crisscross the stage with clockwork precision in heads and feet — captured the ballet’s ingenious choreography, its complex poetry and the marvel of beautiful dancing. We have Ellen Rose Hummel, Lauren Parrott, Julia Rowe and Emma Rubinowitz to thank for that.

The National Portrait Gallery exhibition “Dressed for the Image” takes its title from a Marlene Deitrich interview in which the actress is quoted as saying: “I dress for the image — not for myself, not for the public, not for fashion, not for men.”